During peak demand periods in a day, customers of an electrical utility company may require electrical power at a higher than average supply level. The peak demand periods may last for a number of hours one or more times during the day, may vary with each season of the year, and may vary from region to region. For example, in the summer months, a peak demand period may be between 2:00 PM and 6:00 PM, representing the time when air conditioners are turned on in anticipation of the customers of the electrical utility company returning from work. In the winter months in the northern states of the Untied States, for example, peak demand periods may be between 6:00 AM and 9:00 AM and 2:00 PM and 6:00 PM, respectively representing the times when the heater is turned on in anticipation of the customers of the electrical utility company waking up for work and returning from work. In order to incentivize energy conservation during the peak demand periods, the electrical utility company may increase the cost of energy consumption during the peak demand periods.
An energy consumption strategy (e.g., the pre-cooling strategy) for buildings has been developed with this increase in cost of energy consumption in mind. With the pre-cooling strategy, a whole building is pre-cooled during the non-peak demand period(s), so that a certain amount of thermal mass may be saved. The thermal mass may then be shaded by raising a cooling set point during the peak demand period(s). For example, a cooling period may be specified, and the temperature within the building may be shaded exponentially during the peak demand period(s).
Optimal values for start and end times for the cooling period and an end time for the exponential temperature increase of the pre-cooling strategy (e.g., pre-cooling times) may be determined using a numerical model to exhaustively simulate the cost of energy consumption for the possible combinations of the pre-cooling times. This, however, may result in high computation time and cost, as the number of possible combinations of the pre-cooling times may be high.